/**
 * undo redo
 * @file
 * @since 1.2.6.1
 */

/**
 * 撤销上一次执行的命令
 * @command undo
 * @method execCommand
 * @param { String } cmd 命令字符串
 * @example
 * ```javascript
 * editor.execCommand( 'undo' );
 * ```
 */

/**
 * 重做上一次执行的命令
 * @command redo
 * @method execCommand
 * @param { String } cmd 命令字符串
 * @example
 * ```javascript
 * editor.execCommand( 'redo' );
 * ```
 */

UE.plugins["undo"] = function() {
  var saveSceneTimer;
  var me = this,
    maxUndoCount = me.options.maxUndoCount || 20,
    maxInputCount = me.options.maxInputCount || 20,
    fillchar = new RegExp(domUtils.fillChar + "|</hr>", "gi"); // ie会产生多余的</hr>
  var noNeedFillCharTags = {
    ol: 1,
    ul: 1,
    table: 1,
    tbody: 1,
    tr: 1,
    body: 1
  };
  var orgState = me.options.autoClearEmptyNode;
  function compareAddr(indexA, indexB) {
    if (indexA.length != indexB.length) return 0;
    for (var i = 0, l = indexA.length; i < l; i++) {
      if (indexA[i] != indexB[i]) return 0;
    }
    return 1;
  }

  function compareRangeAddress(rngAddrA, rngAddrB) {
    if (rngAddrA.collapsed != rngAddrB.collapsed) {
      return 0;
    }
    if (
      !compareAddr(rngAddrA.startAddress, rngAddrB.startAddress) ||
      !compareAddr(rngAddrA.endAddress, rngAddrB.endAddress)
    ) {
      return 0;
    }
    return 1;
  }

  function UndoManager() {
    this.list = [];
    this.index = 0;
    this.hasUndo = false;
    this.hasRedo = false;
    this.undo = function() {
      if (this.hasUndo) {
        if (!this.list[this.index - 1] && this.list.length == 1) {
          this.reset();
          return;
        }
        while (
          this.list[this.index].content == this.list[this.index - 1].content
        ) {
          this.index--;
          if (this.index == 0) {
            return this.restore(0);
          }
        }
        this.restore(--this.index);
      }
    };
    this.redo = function() {
      if (this.hasRedo) {
        while (
          this.list[this.index].content == this.list[this.index + 1].content
        ) {
          this.index++;
          if (this.index == this.list.length - 1) {
            return this.restore(this.index);
          }
        }
        this.restore(++this.index);
      }
    };

    this.restore = function() {
      var me = this.editor;
      var scene = this.list[this.index];
      var root = UE.htmlparser(scene.content.replace(fillchar, ""));
      me.options.autoClearEmptyNode = false;
      me.filterInputRule(root);
      me.options.autoClearEmptyNode = orgState;
      //trace:873
      //去掉展位符
      me.document.body.innerHTML = root.toHtml();
      me.fireEvent("afterscencerestore");
      //处理undo后空格不展位的问题
      if (browser.ie) {
        utils.each(
          domUtils.getElementsByTagName(me.document, "td th caption p"),
          function(node) {
            if (domUtils.isEmptyNode(node)) {
              domUtils.fillNode(me.document, node);
            }
          }
        );
      }

      try {
        var rng = new dom.Range(me.document).moveToAddress(scene.address);
        rng.select(
          noNeedFillCharTags[rng.startContainer.nodeName.toLowerCase()]
        );
      } catch (e) {}

      this.update();
      this.clearKey();
      //不能把自己reset了
      me.fireEvent("reset", true);
    };

    this.getScene = function() {
      var me = this.editor;
      var rng = me.selection.getRange(),
        rngAddress = rng.createAddress(false, true);
      me.fireEvent("beforegetscene");
      var root = UE.htmlparser(me.body.innerHTML);
      me.options.autoClearEmptyNode = false;
      me.filterOutputRule(root);
      me.options.autoClearEmptyNode = orgState;
      var cont = root.toHtml();
      //trace:3461
      //这个会引起回退时导致空格丢失的情况
      //            browser.ie && (cont = cont.replace(/>&nbsp;</g, '><').replace(/\s*</g, '<').replace(/>\s*/g, '>'));
      me.fireEvent("aftergetscene");

      return {
        address: rngAddress,
        content: cont
      };
    };
    this.save = function(notCompareRange, notSetCursor) {
      clearTimeout(saveSceneTimer);
      var currentScene = this.getScene(notSetCursor),
        lastScene = this.list[this.index];

      if (lastScene && lastScene.content != currentScene.content) {
        me.trigger("contentchange");
      }
      //内容相同位置相同不存
      if (
        lastScene &&
        lastScene.content == currentScene.content &&
        (notCompareRange
          ? 1
          : compareRangeAddress(lastScene.address, currentScene.address))
      ) {
        return;
      }
      this.list = this.list.slice(0, this.index + 1);
      this.list.push(currentScene);
      //如果大于最大数量了，就把最前的剔除
      if (this.list.length > maxUndoCount) {
        this.list.shift();
      }
      this.index = this.list.length - 1;
      this.clearKey();
      //跟新undo/redo状态
      this.update();
    };
    this.update = function() {
      this.hasRedo = !!this.list[this.index + 1];
      this.hasUndo = !!this.list[this.index - 1];
    };
    this.reset = function() {
      this.list = [];
      this.index = 0;
      this.hasUndo = false;
      this.hasRedo = false;
      this.clearKey();
    };
    this.clearKey = function() {
      keycont = 0;
      lastKeyCode = null;
    };
  }

  me.undoManger = new UndoManager();
  me.undoManger.editor = me;
  function saveScene() {
    this.undoManger.save();
  }

  me.addListener("saveScene", function() {
    var args = Array.prototype.splice.call(arguments, 1);
    this.undoManger.save.apply(this.undoManger, args);
  });

  //    me.addListener('beforeexeccommand', saveScene);
  //    me.addListener('afterexeccommand', saveScene);

  me.addListener("reset", function(type, exclude) {
    if (!exclude) {
      this.undoManger.reset();
    }
  });
  me.commands["redo"] = me.commands["undo"] = {
    execCommand: function(cmdName) {
      this.undoManger[cmdName]();
    },
    queryCommandState: function(cmdName) {
      return this.undoManger[
        "has" + (cmdName.toLowerCase() == "undo" ? "Undo" : "Redo")
      ]
        ? 0
        : -1;
    },
    notNeedUndo: 1
  };

  var keys = {
    //  /*Backspace*/ 8:1, /*Delete*/ 46:1,
    /*Shift*/ 16: 1,
    /*Ctrl*/ 17: 1,
    /*Alt*/ 18: 1,
    37: 1,
    38: 1,
    39: 1,
    40: 1
  },
    keycont = 0,
    lastKeyCode;
  //输入法状态下不计算字符数
  var inputType = false;
  me.addListener("ready", function() {
    domUtils.on(this.body, "compositionstart", function() {
      inputType = true;
    });
    domUtils.on(this.body, "compositionend", function() {
      inputType = false;
    });
  });
  //快捷键
  me.addshortcutkey({
    Undo: "ctrl+90", //undo
    Redo: "ctrl+89" //redo
  });
  var isCollapsed = true;
  me.addListener("keydown", function(type, evt) {
    var me = this;
    var keyCode = evt.keyCode || evt.which;
    if (
      !keys[keyCode] &&
      !evt.ctrlKey &&
      !evt.metaKey &&
      !evt.shiftKey &&
      !evt.altKey
    ) {
      if (inputType) return;

      if (!me.selection.getRange().collapsed) {
        me.undoManger.save(false, true);
        isCollapsed = false;
        return;
      }
      if (me.undoManger.list.length == 0) {
        me.undoManger.save(true);
      }
      clearTimeout(saveSceneTimer);
      function save(cont) {
        cont.undoManger.save(false, true);
        cont.fireEvent("selectionchange");
      }
      saveSceneTimer = setTimeout(function() {
        if (inputType) {
          var interalTimer = setInterval(function() {
            if (!inputType) {
              save(me);
              clearInterval(interalTimer);
            }
          }, 300);
          return;
        }
        save(me);
      }, 200);

      lastKeyCode = keyCode;
      keycont++;
      if (keycont >= maxInputCount) {
        save(me);
      }
    }
  });
  me.addListener("keyup", function(type, evt) {
    var keyCode = evt.keyCode || evt.which;
    if (
      !keys[keyCode] &&
      !evt.ctrlKey &&
      !evt.metaKey &&
      !evt.shiftKey &&
      !evt.altKey
    ) {
      if (inputType) return;
      if (!isCollapsed) {
        this.undoManger.save(false, true);
        isCollapsed = true;
      }
    }
  });
  //扩展实例，添加关闭和开启命令undo
  me.stopCmdUndo = function() {
    me.__hasEnterExecCommand = true;
  };
  me.startCmdUndo = function() {
    me.__hasEnterExecCommand = false;
  };
};
